JN5139/001,531 NXP Semiconductors, JN5139/001,531 Datasheet - Page 25

• Manufacturer Part Number: JN5139/001,531
• Description: MCU 802.15.4 32BIT 2.4G 56-QFN
• Manufacturer: NXP Semiconductors

Specifications of JN5139/001,531

• Frequency: 2.4GHz
• Modulation Or Protocol: 802.15.4
• Applications: General Purpose
• Power - Output: *
• Sensitivity: -96dBm
• Voltage - Supply: 2.7 V ~ 3.6 V
• Current - Receiving: 37mA
• Current - Transmitting: 37mA
• Data Interface: PCB, Surface Mount
• Memory Size: 96kB RAM, 192kB ROM
• Antenna Connector: PCB, Surface Mount
• Operating Temperature: -20°C ~ 70°C
• Package / Case: 56-VFQFN
• Core: RISC
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

8.2 Modem
The Modem performs all the necessary modulation and spreading functions required for digital transmission and
reception of data at 250kbps in the 2450MHz radio frequency band in compliance with the IEEE802.15.4 standard.
The transmitter receives symbols from the baseband processor and uses the spreading function to map each unique
4-bit symbol to a 32-chip Pseudo-random Noise (PN) sequence. Offset-QPSK modulation and half-sine pulse
shaping is applied to the resultant spreading sequence to produce two independent quadrature phase signals (I and
Q), which are subsequently converted to analogue voltages in the radio transmit path.
The Automatic Gain Control (AGC) monitors the received signal level and adjusts the gain of the amplifiers in the
radio receiver to ensure that the optimum signal amplitude is maintained during reception.
The demodulator performs digital IF down-conversion and matched filtering and is extremely tolerant to carrier
frequency offsets in excess of ±80ppm without suffering any significant degradation in performance.
© NXP Laboratories UK 2010
ADO (DIO[12])
TX Active
RX Active
IF Signal
Gain
Q
I
Figure 17 Antenna Diversity ADO Signal for TX with Acknowledgement
Pulse Shaping
AGC
1
st
TX-RX Cycle
Figure 18: Modem Architecture
Q
I
JN-DS-JN5139 1v9
Demodulation
Modulation
O-QPSK
O-QPSK
RX
TX
Q
I
(Despreading)
Spreading
Detection
Symbol
2
nd
TX-RX Cycle (1
st
Retry)
Interface
RX Data
Interface
TX Data
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